#33360 [Bgs]: Pointer to item in $_SESSION superglobal causes troubles
| From: | luca dot fabbro at procne dot it | Date: | Thu, 16 Jun 2005 14:23:37 +0000 |
| Subject: | #33360 [Bgs]: Pointer to item in $_SESSION superglobal causes troubles | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-80447@lists.php.net to get a copy of this message | ||
ID: 33360
User updated by: luca dot fabbro at procne dot it
Reported By: luca dot fabbro at procne dot it
Status: Bogus
Bug Type: Session related
Operating System: Linux
PHP Version: 4.3.10
New Comment:
I'm just a bit confused. When I redeclare $pointer I suppose that a
kind of unset was done on old value of $pointer. I was thinking that
previous references were destroyed. In the loop in fact I'll lose the
ability to unset the pointers if I don't do it before redeclaring
$pointer.
In my example if previous pointers were destroyed I have to notice this
"strange" behaviour only on the last element of array.
If reference is put in a function things of course change as exiting
from the function there is an automatic unset of the local $pointer
variable. In this way the last element of the array isn't a reference
as the previous ones.
Previous Comments:
------------------------------------------------------------------------
[2005-06-16 12:55:28] tony2001@php.net
With "$pointer = &$_SESSION['storage'][$i];" you turn
$_SESSION['storage'][$i]; into a reference.
But:
"Note: If array with references is copied, its values are not
dereferenced. This is valid also for arrays passed by value to
functions."
http://www.php.net/manual/en/language.references.whatdo.php
This is also has nothing to do with _SESSION as it can be reproduce on
this code too:
<?php
$a['storage'][] = array('items'=> 0);
$pointer = &$a['storage'][0];
$gitems = $a['storage'];
$gitems[0]['foo'] = 2;
var_dump($a);
?>
------------------------------------------------------------------------
[2005-06-16 12:35:02] luca dot fabbro at procne dot it
Description:
------------
Seems that once you've declared a pointer to one of the items in
session superglobal any other assignment of a variable to that session
item is alwayys treated as a pointer.
Tested on various versions of php 4.3 till 4.3.1
Register globals are OFF
php 5.0.4 having same error
Reproduce code:
---------------
session_start();
for ($i = 0; $i < 2; $i++)
{
$_SESSION['storage'][$i] = array('items'=>$i);
}
$items = count($_SESSION['storage']);
for ($i = 0; $i < $items; $i++)
{
$pointer = &$_SESSION['storage'][$i];
// unset($pointer); // Uncomment me to let me work properly
}
$gitems = $_SESSION['storage'];
foreach ($gitems as $key=>$val)
{
$gitems[$key]['foo'] = time();
}
Expected result:
----------------
$_SESSION = Array
(
[storage] => Array
(
[0] => Array
(
[items] => 0
)
[1] => Array
(
[items] => 1
)
)
)
Actual result:
--------------
$_SESSION = Array
(
[storage] => Array
(
[0] => Array
(
[items] => 0
[foo] => 1118913576
)
[1] => Array
(
[items] => 1
[foo] => 1118913576
)
)
)
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=33360&edit=1